This invention relates to rotary mechanisms such as trochoidal mechanisms, slant axis rotary mechanisms, or the like. More particularly, the invention relates to such mechanisms used as pumps, compressors, engines, or the like and to improved means for biasing rotor carried seals employed in such mechanisms.
Conventionally, energization of seals in engines, pumps, compressors, or the like is accomplished by using the medium to be sealed when under pressure by bleeding a certain portion of the compressed medium to the underside of the seal in a groove to thereby drive the seal out of the groove and into good sealing engagement with a chamber wall. In such mechanisms, the seals must move through the so-called side clearance of the seal before such sealing can take place. Although motion on the order of 0.04 - 0.08 mm is all that is required, during such side shifting, there is a period when the seal is not engaged with the sides of its groove and is, therefore, permitting leakage of the medium.
In reciprocating mechanisms, such leakage is not a serious problem because of short seal length and a resulting relatively small leakage area. However, in rotary mechanisms, it is an important factor because of the much greater relative seal length as compared to a reciprocating mechanism having the same displacement. Thus, there is a need, in rotary mechanisms, for improved means for energizing seals.